/*
 * ObjectValue.java January 2007
 *
 * Copyright (C) 2007, Niall Gallagher <niallg@users.sf.net>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

package wx.xml.simpleframework.xml.strategy;

/**
 * The <code>ObjectValue</code> is an implementation of a value
 * that represents a object other than an array. Objects described
 * by this can be instantiated and set in to the internal graph
 * so that they can be later retrieved.
 *
 * @author Niall Gallagher
 * @see wx.xml.simpleframework.xml.strategy.Allocate
 */
class ObjectValue implements Value {

    /**
     * This is the value that has been set for this instance.
     */
    private Object value;

    /**
     * This is the type that this object is used to represent.
     */
    private Class type;

    /**
     * Constructor for the <code>ObjectValue</code> object. This is
     * used to describe an object that can be instantiated by the
     * deserialization process and set on the internal graph used.
     *
     * @param type this is the type of object that is described
     */
    public ObjectValue(Class type) {
        this.type = type;
    }

    /**
     * This method is used to acquire an instance of the type that
     * is defined by this object. If the value has not been set
     * then this method will return null as this is not a reference.
     *
     * @return an instance of the type this object represents
     */
    public Object getValue() {
        return value;
    }

    /**
     * This method is used set the value within this object. Once
     * this is set then the <code>getValue</code> method will return
     * the object that has been provided for consistency.
     *
     * @param value this is the value to insert as the type
     */
    public void setValue(Object value) {
        this.value = value;
    }

    /**
     * This is the type of the object instance this represents. The
     * type returned by this is used to instantiate an object which
     * will be set on this value and the internal graph maintained.
     *
     * @return the type of the object that will be instantiated
     */
    public Class getType() {
        return type;
    }

    /**
     * This returns zero as this is an object and will typically
     * not be used to instantiate anything. If the reference is an
     * an array then this can not be used to instantiate it.
     *
     * @return this returns zero regardless of the value type
     */
    public int getLength() {
        return 0;
    }

    /**
     * This method always returns false for the default type. This
     * is because by default all elements encountered within the
     * XML are to be deserialized based on there XML annotations.
     *
     * @return this returns false for each type encountered
     */
    public boolean isReference() {
        return false;
    }
}
